Sleeping in a cavern or grotto might not sound like a luxury getaway, but thanks to a growing number of cave hotels its become an increasingly chic experience. Rest assured, these arent sleeping bags on a rocky floor, but rather accommodationssometimes even opulent onesbuilt directly into natural cavities.Theres a stillness in a cave that just cant be replicated elsewhere. In many ways, it could be seen as the pinnacle of the silent travel trend, since sleeping in a cave can help guests escape the hustle and bustle of ordinary lifewhether thats busyness and stress from work, school, or other people.But cave hotels arent just a symbol of our modern need to leave behind the noise of everyday life. As Spencer Bailey, author of a multivolume books series starting with Design: The Leading Hotels of the World and cofounder of the media company The Slowdown, explains, theres a long history of human connection with caves. I feel like people have always wanted to live, stay, or rest in caves for time immemorial. Its simply an innate human desire, he says. Consider Lascaux in France, which is a cave covered in prehistoric art. Its perhaps one of the earliest cave hotels ever; or Matera, an entire city built on a rocky outcrop in Italy, with a complex of cave dwellings carved into the mountainside, Bailey adds.Jump to today, and lodging in caves is a highly coveted experience. Take The Cave in Hocking Hills, Ohio. The luxurious rental has a waiting list of five yearsyep, its true. From craggy rock house style abodes befitting the Flintstones to sleek stone retreats whitewashed in Greek traditional paint, theres a cave accommodation for every kind of aesthetic. So pack your bags and get ready to stay in some of the most amazing cave hotels in the United States and around the world.